This is a unit of time somewhere between "taking forever", "never going to happen," and officially "when it's done". The actual value of DNF is approximately 14 years. The origin is from the severely protracted development of the game of the same name.
guy: "So looks like GTA 6 is about 0.6DNF right now"
other guy: "Yeah, those leaks seem like a good sign though"
guy: "Yeah, but its taking forever"
other guy: "lol"
the primary package manager in newer versions of Red Hat distros such as RHEL, Rocky Linux, AlmaLinux, and Fedora. It largely replaces the old yum package manager.